1 | /* SPDX-License-Identifier: GPL-2.0-or-later */ |
2 | /* fs/ internal definitions |
3 | * |
4 | * Copyright (C) 2006 Red Hat, Inc. All Rights Reserved. |
5 | * Written by David Howells (dhowells@redhat.com) |
6 | */ |
7 | |
8 | struct super_block; |
9 | struct file_system_type; |
10 | struct iomap; |
11 | struct iomap_ops; |
12 | struct linux_binprm; |
13 | struct path; |
14 | struct mount; |
15 | struct shrink_control; |
16 | struct fs_context; |
17 | struct pipe_inode_info; |
18 | struct iov_iter; |
19 | struct mnt_idmap; |
20 | |
21 | /* |
22 | * block/bdev.c |
23 | */ |
24 | #ifdef CONFIG_BLOCK |
25 | extern void __init bdev_cache_init(void); |
26 | #else |
27 | static inline void bdev_cache_init(void) |
28 | { |
29 | } |
30 | #endif /* CONFIG_BLOCK */ |
31 | |
32 | /* |
33 | * buffer.c |
34 | */ |
35 | int __block_write_begin_int(struct folio *folio, loff_t pos, unsigned len, |
36 | get_block_t *get_block, const struct iomap *iomap); |
37 | |
38 | /* |
39 | * char_dev.c |
40 | */ |
41 | extern void __init chrdev_init(void); |
42 | |
43 | /* |
44 | * fs_context.c |
45 | */ |
46 | extern const struct fs_context_operations legacy_fs_context_ops; |
47 | extern int parse_monolithic_mount_data(struct fs_context *, void *); |
48 | extern void vfs_clean_context(struct fs_context *fc); |
49 | extern int finish_clean_context(struct fs_context *fc); |
50 | |
51 | /* |
52 | * namei.c |
53 | */ |
54 | extern int filename_lookup(int dfd, struct filename *name, unsigned flags, |
55 | struct path *path, struct path *root); |
56 | int do_rmdir(int dfd, struct filename *name); |
57 | int do_unlinkat(int dfd, struct filename *name); |
58 | int may_linkat(struct mnt_idmap *idmap, const struct path *link); |
59 | int do_renameat2(int olddfd, struct filename *oldname, int newdfd, |
60 | struct filename *newname, unsigned int flags); |
61 | int do_mkdirat(int dfd, struct filename *name, umode_t mode); |
62 | int do_symlinkat(struct filename *from, int newdfd, struct filename *to); |
63 | int do_linkat(int olddfd, struct filename *old, int newdfd, |
64 | struct filename *new, int flags); |
65 | |
66 | /* |
67 | * namespace.c |
68 | */ |
69 | extern struct vfsmount *lookup_mnt(const struct path *); |
70 | extern int finish_automount(struct vfsmount *, const struct path *); |
71 | |
72 | extern int sb_prepare_remount_readonly(struct super_block *); |
73 | |
74 | extern void __init mnt_init(void); |
75 | |
76 | int mnt_get_write_access_file(struct file *file); |
77 | void mnt_put_write_access_file(struct file *file); |
78 | |
79 | extern void dissolve_on_fput(struct vfsmount *); |
80 | extern bool may_mount(void); |
81 | |
82 | int path_mount(const char *dev_name, struct path *path, |
83 | const char *type_page, unsigned long flags, void *data_page); |
84 | int path_umount(struct path *path, int flags); |
85 | |
86 | int show_path(struct seq_file *m, struct dentry *root); |
87 | |
88 | /* |
89 | * fs_struct.c |
90 | */ |
91 | extern void chroot_fs_refs(const struct path *, const struct path *); |
92 | |
93 | /* |
94 | * file_table.c |
95 | */ |
96 | struct file *alloc_empty_file(int flags, const struct cred *cred); |
97 | struct file *alloc_empty_file_noaccount(int flags, const struct cred *cred); |
98 | struct file *alloc_empty_backing_file(int flags, const struct cred *cred); |
99 | |
100 | static inline void file_put_write_access(struct file *file) |
101 | { |
102 | put_write_access(inode: file->f_inode); |
103 | mnt_put_write_access(mnt: file->f_path.mnt); |
104 | if (unlikely(file->f_mode & FMODE_BACKING)) |
105 | mnt_put_write_access(mnt: backing_file_user_path(f: file)->mnt); |
106 | } |
107 | |
108 | static inline void put_file_access(struct file *file) |
109 | { |
110 | if ((file->f_mode & (FMODE_READ | FMODE_WRITE)) == FMODE_READ) { |
111 | i_readcount_dec(inode: file->f_inode); |
112 | } else if (file->f_mode & FMODE_WRITER) { |
113 | file_put_write_access(file); |
114 | } |
115 | } |
116 | |
117 | /* |
118 | * super.c |
119 | */ |
120 | extern int reconfigure_super(struct fs_context *); |
121 | extern bool super_trylock_shared(struct super_block *sb); |
122 | struct super_block *user_get_super(dev_t, bool excl); |
123 | void put_super(struct super_block *sb); |
124 | extern bool mount_capable(struct fs_context *); |
125 | int sb_init_dio_done_wq(struct super_block *sb); |
126 | |
127 | /* |
128 | * Prepare superblock for changing its read-only state (i.e., either remount |
129 | * read-write superblock read-only or vice versa). After this function returns |
130 | * mnt_is_readonly() will return true for any mount of the superblock if its |
131 | * caller is able to observe any changes done by the remount. This holds until |
132 | * sb_end_ro_state_change() is called. |
133 | */ |
134 | static inline void sb_start_ro_state_change(struct super_block *sb) |
135 | { |
136 | WRITE_ONCE(sb->s_readonly_remount, 1); |
137 | /* |
138 | * For RO->RW transition, the barrier pairs with the barrier in |
139 | * mnt_is_readonly() making sure if mnt_is_readonly() sees SB_RDONLY |
140 | * cleared, it will see s_readonly_remount set. |
141 | * For RW->RO transition, the barrier pairs with the barrier in |
142 | * mnt_get_write_access() before the mnt_is_readonly() check. |
143 | * The barrier makes sure if mnt_get_write_access() sees MNT_WRITE_HOLD |
144 | * already cleared, it will see s_readonly_remount set. |
145 | */ |
146 | smp_wmb(); |
147 | } |
148 | |
149 | /* |
150 | * Ends section changing read-only state of the superblock. After this function |
151 | * returns if mnt_is_readonly() returns false, the caller will be able to |
152 | * observe all the changes remount did to the superblock. |
153 | */ |
154 | static inline void sb_end_ro_state_change(struct super_block *sb) |
155 | { |
156 | /* |
157 | * This barrier provides release semantics that pairs with |
158 | * the smp_rmb() acquire semantics in mnt_is_readonly(). |
159 | * This barrier pair ensure that when mnt_is_readonly() sees |
160 | * 0 for sb->s_readonly_remount, it will also see all the |
161 | * preceding flag changes that were made during the RO state |
162 | * change. |
163 | */ |
164 | smp_wmb(); |
165 | WRITE_ONCE(sb->s_readonly_remount, 0); |
166 | } |
167 | |
168 | /* |
169 | * open.c |
170 | */ |
171 | struct open_flags { |
172 | int open_flag; |
173 | umode_t mode; |
174 | int acc_mode; |
175 | int intent; |
176 | int lookup_flags; |
177 | }; |
178 | extern struct file *do_filp_open(int dfd, struct filename *pathname, |
179 | const struct open_flags *op); |
180 | extern struct file *do_file_open_root(const struct path *, |
181 | const char *, const struct open_flags *); |
182 | extern struct open_how build_open_how(int flags, umode_t mode); |
183 | extern int build_open_flags(const struct open_how *how, struct open_flags *op); |
184 | struct file *file_close_fd_locked(struct files_struct *files, unsigned fd); |
185 | |
186 | long do_ftruncate(struct file *file, loff_t length, int small); |
187 | long do_sys_ftruncate(unsigned int fd, loff_t length, int small); |
188 | int chmod_common(const struct path *path, umode_t mode); |
189 | int do_fchownat(int dfd, const char __user *filename, uid_t user, gid_t group, |
190 | int flag); |
191 | int chown_common(const struct path *path, uid_t user, gid_t group); |
192 | extern int vfs_open(const struct path *, struct file *); |
193 | |
194 | /* |
195 | * inode.c |
196 | */ |
197 | extern long prune_icache_sb(struct super_block *sb, struct shrink_control *sc); |
198 | int dentry_needs_remove_privs(struct mnt_idmap *, struct dentry *dentry); |
199 | bool in_group_or_capable(struct mnt_idmap *idmap, |
200 | const struct inode *inode, vfsgid_t vfsgid); |
201 | |
202 | /* |
203 | * fs-writeback.c |
204 | */ |
205 | extern long get_nr_dirty_inodes(void); |
206 | void invalidate_inodes(struct super_block *sb); |
207 | |
208 | /* |
209 | * dcache.c |
210 | */ |
211 | extern int d_set_mounted(struct dentry *dentry); |
212 | extern long prune_dcache_sb(struct super_block *sb, struct shrink_control *sc); |
213 | extern struct dentry *d_alloc_cursor(struct dentry *); |
214 | extern struct dentry * d_alloc_pseudo(struct super_block *, const struct qstr *); |
215 | extern char *simple_dname(struct dentry *, char *, int); |
216 | extern void dput_to_list(struct dentry *, struct list_head *); |
217 | extern void shrink_dentry_list(struct list_head *); |
218 | extern void shrink_dcache_for_umount(struct super_block *); |
219 | extern struct dentry *__d_lookup(const struct dentry *, const struct qstr *); |
220 | extern struct dentry *__d_lookup_rcu(const struct dentry *parent, |
221 | const struct qstr *name, unsigned *seq); |
222 | extern void d_genocide(struct dentry *); |
223 | |
224 | /* |
225 | * pipe.c |
226 | */ |
227 | extern const struct file_operations pipefifo_fops; |
228 | |
229 | /* |
230 | * fs_pin.c |
231 | */ |
232 | extern void group_pin_kill(struct hlist_head *p); |
233 | extern void mnt_pin_kill(struct mount *m); |
234 | |
235 | /* |
236 | * fs/nsfs.c |
237 | */ |
238 | extern const struct dentry_operations ns_dentry_operations; |
239 | |
240 | /* |
241 | * fs/stat.c: |
242 | */ |
243 | |
244 | int getname_statx_lookup_flags(int flags); |
245 | int do_statx(int dfd, struct filename *filename, unsigned int flags, |
246 | unsigned int mask, struct statx __user *buffer); |
247 | |
248 | /* |
249 | * fs/splice.c: |
250 | */ |
251 | ssize_t splice_file_to_pipe(struct file *in, |
252 | struct pipe_inode_info *opipe, |
253 | loff_t *offset, |
254 | size_t len, unsigned int flags); |
255 | |
256 | /* |
257 | * fs/xattr.c: |
258 | */ |
259 | struct xattr_name { |
260 | char name[XATTR_NAME_MAX + 1]; |
261 | }; |
262 | |
263 | struct xattr_ctx { |
264 | /* Value of attribute */ |
265 | union { |
266 | const void __user *cvalue; |
267 | void __user *value; |
268 | }; |
269 | void *kvalue; |
270 | size_t size; |
271 | /* Attribute name */ |
272 | struct xattr_name *kname; |
273 | unsigned int flags; |
274 | }; |
275 | |
276 | |
277 | ssize_t do_getxattr(struct mnt_idmap *idmap, |
278 | struct dentry *d, |
279 | struct xattr_ctx *ctx); |
280 | |
281 | int setxattr_copy(const char __user *name, struct xattr_ctx *ctx); |
282 | int do_setxattr(struct mnt_idmap *idmap, struct dentry *dentry, |
283 | struct xattr_ctx *ctx); |
284 | int may_write_xattr(struct mnt_idmap *idmap, struct inode *inode); |
285 | |
286 | #ifdef CONFIG_FS_POSIX_ACL |
287 | int do_set_acl(struct mnt_idmap *idmap, struct dentry *dentry, |
288 | const char *acl_name, const void *kvalue, size_t size); |
289 | ssize_t do_get_acl(struct mnt_idmap *idmap, struct dentry *dentry, |
290 | const char *acl_name, void *kvalue, size_t size); |
291 | #else |
292 | static inline int do_set_acl(struct mnt_idmap *idmap, |
293 | struct dentry *dentry, const char *acl_name, |
294 | const void *kvalue, size_t size) |
295 | { |
296 | return -EOPNOTSUPP; |
297 | } |
298 | static inline ssize_t do_get_acl(struct mnt_idmap *idmap, |
299 | struct dentry *dentry, const char *acl_name, |
300 | void *kvalue, size_t size) |
301 | { |
302 | return -EOPNOTSUPP; |
303 | } |
304 | #endif |
305 | |
306 | ssize_t __kernel_write_iter(struct file *file, struct iov_iter *from, loff_t *pos); |
307 | |
308 | /* |
309 | * fs/attr.c |
310 | */ |
311 | struct mnt_idmap *alloc_mnt_idmap(struct user_namespace *mnt_userns); |
312 | struct mnt_idmap *mnt_idmap_get(struct mnt_idmap *idmap); |
313 | void mnt_idmap_put(struct mnt_idmap *idmap); |
314 | struct stashed_operations { |
315 | void (*put_data)(void *data); |
316 | int (*init_inode)(struct inode *inode, void *data); |
317 | }; |
318 | int path_from_stashed(struct dentry **stashed, struct vfsmount *mnt, void *data, |
319 | struct path *path); |
320 | void stashed_dentry_prune(struct dentry *dentry); |
321 | |